A rectangular courtyard with length 3 m 85 cm and breadth 2 m 52 cm is to be paved with square stones of the same size. Find the least number of such stones required.

Gerhard drove 45.696 km to visit his grandmother. When he reached his grandmother's house he noticed that the car had used up 3.36 liters of petrol. How many kilometers did he travel per liter of petrol?